1. Technical Field
The present invention relates to a liquid ejecting head that includes a piezoelectric element having a piezoelectric layer formed of a piezoelectric material and an electrode and discharges droplets from a nozzle opening, a liquid ejecting apparatus, and a piezoelectric element.
2. Related Art
As the piezoelectric element used in the liquid ejecting head, there has been a piezoelectric element that is configured so that a piezoelectric layer formed of a piezoelectric material presenting an electromechanical conversion function, for example, a crystallized dielectric material is interposed between two electrodes. Such a piezoelectric element is mounted on, for example, a liquid ejecting head as a bending vibration mode actuator device. Herein, as a representative example of the liquid ejecting head, for example, there has been an ink jet type recording head in which a part of a pressure generating chamber communicating with a nozzle opening ejecting ink droplets is constituted by a vibration plate, and the vibration plate is deformed by the piezoelectric element, and ink in the pressure generating chamber is pressurized and is discharged as ink droplets from the nozzle opening.
The piezoelectric material used as the piezoelectric layer forming such a piezoelectric element requires high piezoelectric characteristics, and lead zirconate titanate (PZT) is adopted as a representative example of the piezoelectric material (see JP-A-2001-223404). However, lead zirconate titanate contains lead, and from the viewpoint of environmental problems, there is a need for a piezoelectric material that does not contain lead. Thus, as a piezoelectric material that does not contain lead, a bismuth-based piezoelectric material, for example, a piezoelectric material having a bismuth ferrate-based (BiFeO3-based) perovskite structure containing bismuth and iron has been proposed. As a specific example, there is a complex oxide expressed by a mixed crystal of bismuth ferrate manganate such as Bi(Fe, Mn)O3 and barium titanate such as BaTiO3 (for example, see JP-2009-252789).
However, there was a problem that the piezoelectric layer formed of such a complex oxide has low displacement characteristics compared to lead zirconate titanate. For this reason, high displacement characteristics are demanded.
In addition, of course, such a problem is also similarly present in other liquid ejecting heads that discharge droplets other than ink as well as the ink jet type recording head, and is also similarly present in the piezoelectric element used in other devices than the liquid ejecting head.